Multi-circuit switch with improved castellated sections



March 7, 1967 w. CULLEN 3,308,249

MULTI-CIRCUIT SWITCH WITH IMPROVED CASTELLATED SECTIONS 5 Sheets-Sheet 1 Filed March 30. 1966 March 7, 1967 G. w. CULLEN 3,308,249

MULTI-CIRCUIT SWITCH WITH IMPROVED CASTELLATED SECTIONS Filed March so. 1966 a Sheets-Sheet 5 3,3fi8,249 Patented Mar. 7, 1967 tit 3,308,249 MULTI-CIRCUIT SWITCH WITH IMPROVED CASTELLATED SECTIONS Geoffrey W. Cullen, Sarishury, Southampton, England, assignor to The Plessey Company Limited, Ilford, England, a British company Filed Mar. 30, 1966, Ser. No. 538,618 Claims priority application Great Britain, Apr. 2, 1965, 14,116/ 65 3 Claims. (Cl. 20014) This invention relates to rotary electric switch constructions. It is an object of the invention to provide an improved rotary electric switch construction which is such that the number of contacts can be varied without modifying the supporting members for the contacts.

According to the invention there is provided a rotary electric switch including at least two contact supporting members which are castellated, the castellations being cooperably interengaged and a contact element clamped be tween co-operating castellations.

If desired more than one such contact element may be provided, each being clamped between a different palr of co-operating castellations. Moreover the contact element of each such element may be further secured between the respective pair of co-operating castellations by use of lacquer or adhesive material or by the provision of enlarged portions of the contact element arranged to lie on each side of the walls of the co-operating castellations, or, in a preferred arrangement, said castellations may be so shaped that they co-operate with each other in a plane inclined to the radial direction of the switch and the contact element or each such element is so shaped as to be clamped between said castellations in said irrcli'ned plane thereby preventing relative movement of sald contact element to said co-operating castellations in the radial directions.

The contact supporting members may form a part of a stator assembly and may comprise plastics mouldings of generally cylindrical shape which when co-operably interconnected define a cylindrical enclosure for accommodatin-g a rotor assembly including a shaft extending coaxially through said supporting members.

In order that the invention may be clearly understood and readily carried into effect it will now be more fully described with reference to the accompanying drawings, in which:

FIGURE 1 is a side elevation of a rotary electric switch in accordance with one embodiment of the invention,

FIGURE 2 is a perspective view, on an enlarged scale, of a portion of the switch of FIGURE 1.

FIGURE 3 is a perspective view, partly cut away, of a rotary electric switch in accordance with another embodiment of the invention,

FIGURE 4 is a plan view of part of the switch of FIG- URE 3, and

FIGURE 5 is a side elevation of the part of FIGURE 4.

Referring first to the embodiment of FIGURES 1 and 2 of the drawings, the switch includes a rotor assembly 11 together with a base stator member 12 and at least one additional stator member 13, the members 12 and 13 constituting contact supporting members. The base member 12 comprises a cup-shaped member with a flat base and a cylindrical wall, the free end of the wall being castellated. A through bore is formed in the base of the member 12. In addition a rotor shaft bearing unit 14 is attached to or formed integrally with the base of said member 12. This unit 14 includes a conventionally threaded boss 15 which enables the switch to be mounted on a base board or panel. If desired the base of the member 12 can be provided with a locating lug 16 whereby the switch can be orientated in a particular direction to the base board or panel.

Each additional stator member 13 has a cylindrical wall with internal and external diameters corresponding to those of the wall of the base stator member 12 and an internally directed annular flange located intermediate of the ends of the cylindrical Wall. The diameter of the bore in the flange 13a is intended to be a clearance fit with respect to a shaft 17 of the rotor assembly so that the rotor can be effectively rotatably journalled in the annular flanges 13a of all the additional stator members 13. Each end of the cylindrical Wall of each member 13 is castellated so that when two of the additional stator members 13 or a base stator member 12 and an additional stator member 13 are coaxially arranged i.e. with their end castellated walls face-to-face the facing castellations will co-operably interconnect with one another. With this arrangement the co-operating castellations define opposing surfaces in planes which are orthogonal to the axis of the switch which surfaces can be used to locate and grip between them stator contact elements 18 of the switch. The stator contact elements 18 extend radially of the members 12 and 13 towards the axis of the switch, i.e. said contact elements 18 lie in the aforesaid orthogonal planes. The radial dimensions of the contact elements 18 are such that the actual contact pips or other like contact areas of the contact elements are located at a required axial distance from the axis of the switch.

The rotor assembly 11 for the switch includes the rotor shaft 17 which is rotatably jo-urnalled in the base stator member 12 by means of a bearing unit 14 as well as in the flanges 13a and a series of insulated annular rotor contact carrying elements 19, each carrying rotor contacts 20, and which elements 19 are so mounted on the rotor shaft 17 that the rotor contacts 20 can co-operate with the stator contact elements 18 to bridge selected pairs of said elements 18 according to the angular position of the shaft 17.

Preferably the rotor contacts 20 are such as to provide a continuous wipe with the stator contact elements 18.

A rotary electric switch as above described can be assembled as follows. A first rotor contact carrying element 19 is mounted on the shaft 17 in a first prede termined position, this position coinciding substantially with the castellations of the base stator member 12. The required number of stator contact elements 18 are then placed in the recesses between adjacent castellations of the base stator member 12 so that said elements 18 lie in planes orthogonal to the axis of the switch and are in contact with the first rotor carrying element 19. A first additional castellated stator member 13 is then applied over the rotor shaft 17 and arranged with its castellations at one end cooperating with the castellations on the base stator member 12 thereby firmly gripping and locating the stator contact elements 18 positioned between the castellations on said base stator member 12. If a second bank of stator contact elements 18 is required a second rotorcontact carrying element 19 with its rotor contacts 26 is mounted on the shaft 17 and a second set of stator contact elements 18 is located in the recesses between the castellations at the other end of the first additional stator member 13. A second additional stator member 13 is then placed in position With its castellations at one end co-operating with the castellations at said other end of the first additional castellated shaft or member 13 so as to hold the second set of stator contact elements 18 in place.

If further banks of stator contact elements 18 and rotor contacts 20 are required further of said additional stator members 13 are provided and the further stator contact elements 18 are mounted in the same manner as described. When the required number of banks have been attained locking means (not shown) are provided for holding the stator members 12, 13 onto the rotor shaft 17. Conveniently this can be a circlip or other suitable arrangement.

If an indexing mechanism is required in the rotary switch a conventional pip and hole or other suitable indexing arrangement (not shown) can be provided in the base stator member. In this case the rot-or shaft 17 could be provided with a plate having a number of holes which are engaged by pips on a plate secured relative to the base of the base stator member.

For convenience the additional stator member which is intended to form the end member of a completed switch remote from the base member 12 can be of a cup-shaped construction, i.e. the intermediate annular flange 13a may be displaced to form an end wall of the end member.

If desired the stator contact elements 18 can be fixedly attached to one or both of the associated stator members 12 or 13. For example a lacquer or adhesive could be used. For the purposes of ventilation, and for drainage, -a vent hole 21 (FIGURE 1) can be provided in each stator member cylindrical wall. It will be understood that the above described stator construction could be used with an annular rotor, i.e. the stator being located within the rotor. Furthermore, the above described construction could be applied to the rotor assembly. The above described switch can be of compact construction. By way of example five banks of contacts may be accommodated in an overall length of less than two inches with an external diameter for the stator elements of less than A.

In an alternative method of ensuring that the contact elements 18 are not displaced in the radial direction, i.e. lengthwise of the Contact elements, said elements 18 may be formed with enlarged portions whereby shoulders are provided positioned to engage on opposite sides of the Walls of the co-operating castellated stator members. By way of example the contact elements 18 may be stamped out of sheet material, and the enlarged portions can be stamped out simultaneously.

An embodiment of the invention employing yet another, and preferred, arrangement for precluding radial displacement of the contact elements is illustrated in F IG- URES 3 to of the accompanying drawings. In this embodiment the rotary electric switch again comprises an inner rotor shaft 31 mounted in a bearing unit 32, and a stator assembly surrounding and coaxial with said shaft 31. The stator assembly comprises a base stator member 33, similar to the base member 12 of FIGURE 1, having a castellated wall co-operating with a castellated Wall of an additional stator member 34. Between selected ones of said co-operating castellations there are clamped contact elements 35 in a manner which will be more fully described hereinafter.

The additional stator member 34, unlike the additional stator members 13 of the embodiment of FIGURE 1, has castellations at only one end of its cylindrical wall, the other end being terminated by a flat base which is arranged in contact with the flat base 36 of a further similar additional stator member 37. Alternatively, however, the two additional stator members 34 and 3'7 may be integral with each other, the flat bases being replaced by an inwardly directed flange intermediate the castellated ends of the members 33 and 37, i.e. similarly to the additional stator members 13 of the embodiment of FIG URE 1 although, as will become apparent hereinafter, the diameter of member 34 is, in this embodiment, less than the diameter of member 37. The castellations 38 of the additional stator member 37 are arranged to cooperate with castellations 39 of yet another additional stator member 40. The additional stator member 40 has flat base and a cylindrical wall portion 41, the end of which remote from the base has said castellations 39. The member 40 is shown in detail in FIGURES 4 and 5. Contact elements 35 are clamped between selected ones of said co-operating castellations 38 and 39.

The configuration of the contact elements 35 is shown in the cut away portion of FIGURE 3. Each element 35 extends generally radially inwardly with respect to the axis of the switch and includes at its innermost end a pair of opposed wiper contacts 4-2. The part of the element 35 which is clamped between co-operating castellations includes a first portion 43 which is substantially radial and a second outer portion 44 which is inclined to said radial direction as shown. Moreover the castellated ends of the members 37 and as are provided with two corresponding pairs of co-operating surfaces, the first pair being radial of the switch to clamp the portion 43 of the element 35 and the second pair being inclined to said radial direction to clamp the portion 44 of said element 35. In the case of the members 37 and 4d the recesses between the castellations 38 of members 37 are provided with said first and second surfaces as indicated by references 45 and 4.6 respectively, While the castellations of the member 40 are arranged to fit against said surfaces 45 and 46 to clamp the portions 43 and 44 of a respective contact element 35. Thus it will be appreciated that the castellations of two contact supporting members cooperate with each other in two mutually inclined planes. In this way movement of the contact elements 35 of the switch with respect to the stator assembly is precluded. Moreover, in the particular embodiment shown in FIG- URE 3 the member 4% lies substantially within the confines of the member 37 so that it can 'be arranged that the overall depth of the switch is independent of tolerances in the thickness of the contact elements 35.

The wiper contacts 4-2 of the contact elements 35 in each bank of such elements are arranged to co-operate with a rotor contact carrying element 47 having suitable contacts 48 formed thereon, for example by printed circuit technique. The rotor contact carrying element 47 is secured to a fiat extension 31a of the shaft 31 so as to be rotated with said shaft 31 and thus to afford various connections between the rotor and stator contacts in dependence upon the angular position of the shaft 31. It will be appreciated that the flat bases of the stator members are apertured to accommodate the extension of the shaft 31.

Indexing means for the switch may be provided, for example on the base stator member 33 as described with reference to the embodiment of FIGURE 1.

Although the invention has been described with particular reference to specific embodimentsthereof as illustrated in the drawings various modifications may be made to these embodiments without departing from the scope of the invention as set out in the appendent claims. By way of example the two co-operating surfaces of the castellations in the embodiment of FIGURE 3 may be at right angles to each other. Moreover, as in the embodiment of FIGURES 1 and 2 the stator may be located within an annular rotor. If desired the above described construction of castellated supporting members clamping between them contact elements may be applied to the rotor of a switch.

I claim:

I. A rotary electric switch comprising a stator, a rotor, actuating means for facilitating rotation of said rotor with respect to said stator, said stator including at least two insulating contact supporting members secured together, said secured supporting members having castellations interlocking with each other, at least one contact element lying in a radial plane relative to the axis of rotation of said rotor and clamped between said interlocking castellations, said castellations having clamping surfaces lying in planes transverse to said radial plane to preclude displacement of said clamped contact element relative to said supporting members, said rotor having contacts co- 5 6 operable with said clamped contact element to effect dif- References Cited by the Examiner ggrignltosigtching actions in diflerent angular positions of UNITED STATES PATENTS 2. A rotary electric switch as defined in claim 1 wherein 2,971,174 2/1961 Lyonsaid castellations have further cooperating surfaces 5 3,177,306 4/1965 Mastney 20014 X which lie in Said radial plane. 3,242,273 3/ 1966 Van Der Put 200l6 3. A rotary electric switch as defined in claim 2, Wherel in one of said cooperating contact supporting members ROBERT SCHAEFER Pnma'y Examiner lies within the confines of the other. I. R. SCOTT, Assistant Examiner. 

1. A ROTARY ELECTRIC SWITCH COMPRISING A STATOR, A ROTOR, ACTUATING MEANS FOR FACILITATING ROTATION OF SAID ROTOR WITH RESPECT TO SAID STATOR, SAID STATOR INCLUDING AT LEAST TWO INSULATING CONTACT SUPPORTING MEMBERS SECURED TOGETHER, SAID SECURED SUPPORTING MEMBERS HAVING CASTELLATIONS INTERLOCKING WITH EACH OTHER, AT LEAST ONE CONTACT ELEMENT LYING IN A RADIAL PLANE RELATIVE TO THE AXIS OF ROTATION OF SAID ROTOR AND CLAMPED BETWEEN SAID INTERLOCKING CASTELLATIONS, SAID CASTELLATIONS HAVING CLAMPING SURFACES LYING IN PLANES TRANSVERSE TO SAID RADIAL PLANE TO PRECLUDE DISPLACEMENT OF SAID CLAMPED CONTACT ELEMENT RELATIVE TO SAID SUPPORTING MEMBERS, SAID ROTOR HAVING CONTACTS COOPERABLE WITH SAID CLAMPED CONTACT ELEMENT TO EFFECT DIFFERENT SWITCHING ACTIONS IN DIFFERENT ANGULAR POSITIONS OF SAID ROTOR. 